Quite often I find myself taking nighttime photos using my camera's Bulb setting and shutter extension cable in the locked position. I was wondering, how difficult it would be to write a program that would let you control the duration of an exposure when the camera is set at 'B"? Would anyone else find a program like this useful?

I think you are describing a control that acts as a single-function trigger? I'd been thinking about implementing that but I currently just set a shutter speed on one of the test buttons of the bracketer and use that to trigger each shot. If you could confirm that you want just a shot length and a trigger, I can whip that up, or are you describing a trigger that must be held down for the duration of the shot? That is easily doable as well. (I should probably write both?)

Basically, a simple program that will let me control the duration of an exposure with my camera set in 'B' mode. For instance, say I am taking pictures of the night sky and I want a 4 minute long exposure. I would like something that would essentially replace the need for me to lock my shutter release and manually time the exposure.

This must have been lost in the ether, but it should be easily implemented. I'm off to Arizona for a week of filming, I'll bring the dev system along to see if I can find the time to code this. I'm assuming you'll want an on-off toggle and a clock display? Should the gui be red for night vision?

I could see a couple ways of doing it:a) press button to open shutter, press button to close shutter.b) press and hold button to open shutter, release button to close shutter

'b' replicates typical SLR behavior (and good for exposures under 5 seconds), but 'a' would be nicer for longer exposures.

Ideal might be for the application to be able to differentiate between a press and a press-and-hold and support both behaviors (ie: a press that lasts longer than 1.5 seconds = press-and-hold). But, recognizing that might be too much to ask for, I'd say 'a' (press to open, press to close).

As for the colour, red for night vision would be perfect (toggle to normal would be a nice-to-have, but there will be few times that long exposures would be used in good light).

I should apologize, I should have coded this, I just can't find a free minute. I'll be spending a few days on the HMS Surprise next week, and I promise I'll find the time to write this during long nights on deck.

Awesome! I really like the ability to set the delay length and the shot length.

Would it be possible to add the ability to open the shutter with a button press and close it with another button press? (I'm thinking specifically about photographing fireworks, where you may not know exactly how long you want the shutter to be open)